/*
 * FreeRTOS V202012.00
 * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * http://www.FreeRTOS.org
 * http://aws.amazon.com/freertos
 *
 * 1 tab == 4 spaces!
 */

/*
Changes from V1.2.3
	
	+ The created tasks now include calls to tskYIELD(), allowing them to be used
	  with the cooperative scheduler.
*/

/**
 * This does the same as flop. c, but uses variables of type long instead of 
 * type double.  
 *
 * As with flop. c, the tasks created in this file are a good test of the 
 * scheduler context switch mechanism.  The processor has to access 32bit 
 * variables in two or four chunks (depending on the processor).  The low 
 * priority of these tasks means there is a high probability that a context 
 * switch will occur mid calculation.  See the flop. c documentation for 
 * more information.
 *
 * \page IntegerC integer.c
 * \ingroup DemoFiles
 * <HR>
 */

/*
Changes from V1.2.1

	+ The constants used in the calculations are larger to ensure the
	  optimiser does not truncate them to 16 bits.
*/

#include <stdlib.h>

/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "print.h"

/* Demo program include files. */
#include "integer.h"

#define intgSTACK_SIZE		( ( unsigned short ) 256 )
#define intgNUMBER_OF_TASKS  ( 8 )

/* Four tasks, each of which performs a different calculation on four byte 
variables.  Each of the four is created twice. */
static void vCompeteingIntMathTask1( void *pvParameters );
static void vCompeteingIntMathTask2( void *pvParameters );
static void vCompeteingIntMathTask3( void *pvParameters );
static void vCompeteingIntMathTask4( void *pvParameters );

/* These variables are used to check that all the tasks are still running.  If a 
task gets a calculation wrong it will stop incrementing its check variable. */
static volatile unsigned short usTaskCheck[ intgNUMBER_OF_TASKS ] = { ( unsigned short ) 0 };
/*-----------------------------------------------------------*/

void vStartIntegerMathTasks( unsigned portBASE_TYPE uxPriority )
{
	xTaskCreate( vCompeteingIntMathTask1, "IntMath1", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 0 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask2, "IntMath2", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 1 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask3, "IntMath3", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 2 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask4, "IntMath4", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 3 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask1, "IntMath5", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 4 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask2, "IntMath6", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 5 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask3, "IntMath7", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 6 ] ), uxPriority, NULL );
	xTaskCreate( vCompeteingIntMathTask4, "IntMath8", intgSTACK_SIZE, ( void * ) &( usTaskCheck[ 7 ] ), uxPriority, NULL );
}
/*-----------------------------------------------------------*/

static void vCompeteingIntMathTask1( void *pvParameters )
{
long l1, l2, l3, l4;
short sError = pdFALSE;
volatile unsigned short *pusTaskCheckVariable;
const long lAnswer = ( ( long ) 74565L + ( long ) 1234567L ) * ( long ) -918L;
const char * const pcTaskStartMsg = "Integer math task 1 started.\r\n";
const char * const pcTaskFailMsg = "Integer math task 1 failed.\r\n";

	/* Queue a message for printing to say the task has started. */
	vPrintDisplayMessage( &pcTaskStartMsg );

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( unsigned short * ) pvParameters;

	/* Keep performing a calculation and checking the result against a constant. */
	for(;;)
	{
		l1 = ( long ) 74565L;
		l2 = ( long ) 1234567L;
		l3 = ( long ) -918L;

		l4 = ( l1 + l2 ) * l3;

		taskYIELD();

		/* If the calculation does not match the expected constant, stop the
		increment of the check variable. */
		if( l4 != lAnswer )
		{
			vPrintDisplayMessage( &pcTaskFailMsg );
			sError = pdTRUE;
		}

		if( sError == pdFALSE )
		{
			/* If the calculation has always been correct, increment the check
			variable so we know	this task is still running okay. */
			( *pusTaskCheckVariable )++;
		}
	}
}
/*-----------------------------------------------------------*/

static void vCompeteingIntMathTask2( void *pvParameters )
{
long l1, l2, l3, l4;
short sError = pdFALSE;
volatile unsigned short *pusTaskCheckVariable;
const long lAnswer = ( ( long ) -389000L / ( long ) 329999L ) * ( long ) -89L;
const char * const pcTaskStartMsg = "Integer math task 2 started.\r\n";
const char * const pcTaskFailMsg = "Integer math task 2 failed.\r\n";

	/* Queue a message for printing to say the task has started. */
	vPrintDisplayMessage( &pcTaskStartMsg );

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( unsigned short * ) pvParameters;

	/* Keep performing a calculation and checking the result against a constant. */
	for( ;; )
	{
		l1 = -389000L;
		l2 = 329999L;
		l3 = -89L;

		l4 = ( l1 / l2 ) * l3;

		taskYIELD();

		/* If the calculation does not match the expected constant, stop the
		increment of the check variable. */
		if( l4 != lAnswer )
		{
			vPrintDisplayMessage( &pcTaskFailMsg );
			sError = pdTRUE;
		}

		if( sError == pdFALSE )
		{
			/* If the calculation has always been correct, increment the check
			variable so we know this task is still running okay. */
			( *pusTaskCheckVariable )++;
		}
	}
}
/*-----------------------------------------------------------*/

static void vCompeteingIntMathTask3( void *pvParameters )
{
long *plArray, lTotal1, lTotal2;
short sError = pdFALSE;
volatile unsigned short *pusTaskCheckVariable;
const unsigned short usArraySize = ( unsigned short ) 250;
unsigned short usPosition;
const char * const pcTaskStartMsg = "Integer math task 3 started.\r\n";
const char * const pcTaskFailMsg = "Integer math task 3 failed.\r\n";

	/* Queue a message for printing to say the task has started. */
	vPrintDisplayMessage( &pcTaskStartMsg );

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( unsigned short * ) pvParameters;

	/* Create the array we are going to use for our check calculation. */
	plArray = ( long * ) pvPortMalloc( ( size_t ) 250 * sizeof( long ) );

	/* Keep filling the array, keeping a running total of the values placed in the
	array.  Then run through the array adding up all the values.  If the two totals
	do not match, stop the check variable from incrementing. */
	for( ;; )
	{
		lTotal1 = ( long ) 0;
		lTotal2 = ( long ) 0;

		for( usPosition = 0; usPosition < usArraySize; usPosition++ )
		{
			plArray[ usPosition ] = ( long ) usPosition + ( long ) 5;
			lTotal1 += ( long ) usPosition + ( long ) 5;
		}

		taskYIELD();

		for( usPosition = 0; usPosition < usArraySize; usPosition++ )
		{
			lTotal2 += plArray[ usPosition ];
		}

		if( lTotal1 != lTotal2 )
		{
			vPrintDisplayMessage( &pcTaskFailMsg );
			sError = pdTRUE;
		}

		taskYIELD();

		if( sError == pdFALSE )
		{
			/* If the calculation has always been correct, increment the check
			variable so we know	this task is still running okay. */
			( *pusTaskCheckVariable )++;
		}
	}
}
/*-----------------------------------------------------------*/

static void vCompeteingIntMathTask4( void *pvParameters )
{
long *plArray, lTotal1, lTotal2;
short sError = pdFALSE;
volatile unsigned short *pusTaskCheckVariable;
const unsigned short usArraySize = 250;
unsigned short usPosition;
const char * const pcTaskStartMsg = "Integer math task 4 started.\r\n";
const char * const pcTaskFailMsg = "Integer math task 4 failed.\r\n";

	/* Queue a message for printing to say the task has started. */
	vPrintDisplayMessage( &pcTaskStartMsg );

	/* The variable this task increments to show it is still running is passed in
	as the parameter. */
	pusTaskCheckVariable = ( unsigned short * ) pvParameters;

	/* Create the array we are going to use for our check calculation. */
	plArray = ( long * ) pvPortMalloc( ( size_t ) 250 * sizeof( long ) );

	/* Keep filling the array, keeping a running total of the values placed in the 
	array.  Then run through the array adding up all the values.  If the two totals 
	do not match, stop the check variable from incrementing. */
	for( ;; )
	{
		lTotal1 = ( long ) 0;
		lTotal2 = ( long ) 0;

		for( usPosition = 0; usPosition < usArraySize; usPosition++ )
		{
			plArray[ usPosition ] = ( long ) usPosition * ( long ) 12;
			lTotal1 += ( long ) usPosition * ( long ) 12;	
		}

		taskYIELD();
	
		for( usPosition = 0; usPosition < usArraySize; usPosition++ )
		{
			lTotal2 += plArray[ usPosition ];
		}


		if( lTotal1 != lTotal2 )
		{
			vPrintDisplayMessage( &pcTaskFailMsg );
			sError = pdTRUE;
		}

		taskYIELD();

		if( sError == pdFALSE )
		{
			/* If the calculation has always been correct, increment the check 
			variable so we know	this task is still running okay. */
			( *pusTaskCheckVariable )++;
		}
	}
}
/*-----------------------------------------------------------*/

/* This is called to check that all the created tasks are still running. */
portBASE_TYPE xAreIntegerMathsTaskStillRunning( void )
{
/* Keep a history of the check variables so we know if they have been incremented 
since the last call. */
static unsigned short usLastTaskCheck[ intgNUMBER_OF_TASKS ] = { ( unsigned short ) 0 };
portBASE_TYPE xReturn = pdTRUE, xTask;

	/* Check the maths tasks are still running by ensuring their check variables 
	are still incrementing. */
	for( xTask = 0; xTask < intgNUMBER_OF_TASKS; xTask++ )
	{
		if( usTaskCheck[ xTask ] == usLastTaskCheck[ xTask ] )
		{
			/* The check has not incremented so an error exists. */
			xReturn = pdFALSE;
		}

		usLastTaskCheck[ xTask ] = usTaskCheck[ xTask ];
	}

	return xReturn;
}
